tldr: Jack Straw is in E major, mixolydian mode. Almost all of the chords are straight from E mixolydian. In the main verses, the only non-mixolydian chords are:
- a chromatic Imaj7 chord (Emaj7) transitioning from the I to bVII chord (on “mine…” and, later, “sky…”), and
- in the same spot of the second half of the main verses, a major V chord (B) between the I and IV chords (on “slow…” and “sea…”).
The watchman part is E7sus4 & E7 to F#7sus4 & F#7, temporarily modulating up a whole step from E major, mixolydian to F# major, mixolydian. The bridge returns to E major, mixolydian, with purely diatonic chords. At the end of that is a bVII – bIII (D – G) transition, with the G borrowed from E minor, that ends with a chromatic walk down to the E chord, G-Gb-F-E.
Jack Straw Full Analysis
This song is in the key of E major, using the mixolydian mode, and opens with an extended E chord that alternates back with an Esus4. You can play it with beautiful open chords at the seventh fret (0769×0 to 0779×0 and back), or barre chords at the fourth fourth fret (076454, and moving your pinky to add the sus4 by changing that 6 to a 7), or even the low open E chord (022100 to 022200). Jerry sometimes leads into it with a nice little intro that you can make your own. The core of it is basically:
-------------------------- -------------------------- -13-11-9------------------ ---------11--9-11-9-7-6--- ------------------------7- --------------------------
Those notes all happen to be shared between E natural major and E mixolydian (i.e., it omits both D# and D, the natural or flat 7th note), or you could view it as the E major pentatonic plus the added 4th degree note, A. But you aren’t restricted to that; use any of those scales, including the notes he omitted.
The main verse chords are almost all drawn from the E mixolydian mode. That means a minor V chord, Bm, instead of major, and a major bVII chord, D, instead of a diminished vii chord. The chords are:
1. E – F#m – C#m – A (I – ii -vi – IV)
2. E – Bm – D – A – E – Ema7 – D – A (I – v – bVII – IV – I – Ima7 – bVII – IV)
3. Repeat 1
4. Repeat 2 through the second E, then replace Ema7 – D – A with B – A (or V – IV).
There are two non-mixolydian chords here. The first is the Imaj7 passing chord (Emaj7), which does two things. First, it just sounds nice, in that it walks down chromatically from the I to bVII chords (on “mine…” and, later, “sky…”). That is, the starting I chord, E major (E G# B) and target bVII chord, D major (D F# A) have a half-step gap between B and A, and adding in the D# of Emaj7 gives another half step between the D# and D of the D major chord, or E – D# – D. Half-steps have a leading quality, drawing your ear to the next note, so the Emaj7 is just a transition chord that adds more “pull” towards the D chord.
The second function of the Emaj7, in my opinion, is re-emphasizing the E tonic. The parent scale of E mixolydian happens to be A major, meaning that E mixolydian consists of the notes of A major played in the key of E. When using modes and borrowed chords, there is a risk of losing the sense of key and the chords being heard in the context of their natural keys. Ending a phrase on a bVII to IV chord, D to A, could introduce confusion by sounding like a IV chord resolving to a I in the key of A. Using the Emaj7, with its D# note that distinguishes the key of E major and A major, tells the ear that we’re still in the key of E.
The other non-mixolydian chord, B, has less of a chromatic role, and instead serves this latter function. As a major V instead of minor v, used between the I and IV chords, it both strongly reinforces the E tonic (with its D#) and creates the V – IV – I resolution that is common in rock music. And it’s used so briefly that it doesn’t negate the mixolydian quality of the song.
Next, the watchman part goes from E7sus4 to E7, then up two frets to do the same thing with F#7sus4 to F#7. You could the E7 parts as x-7-7-7-x-x to x-7-6-7-x-x or x-x-9-7-10-x to x-x-9-7-9 (and then shifting up two frets). If you do fills with this, E mixolydian works over the E7 chords, and Jerry uses F# mixolydian for nice, bending fills over the F#7 chords.
Note that the F#7 is a major chord, whereas the equivalent chord from E mixolydian would have been F#m7. I initially thought that this F#7 chord was borrowed from the Lydian mode, but I think that was a mistake. The extended length of time in which the F#7 is used, and the fact that the same pattern is just moved up from E to F#, now seems to me to be a temporary modulation from the key of E major (mixolydian mode) to the key of F# major (mixolydian mode).
Then, there’s a great repeating E mixolydian bridge of D-Bm-A-A-E, over which you can do lead using, of course, E mixolydian.
Finally, the bridge ends with a D-G-D-G, and then the G walks in major chords chromatically down the fretboard to E, meaning G-Gb-F-E. The G chord itself, a bIII chord, is not from E mixolydian, but rather borrowed from the parallel minor key, E minor. In fact, the resulting progression — bVII – bIII – I — is basically a minor progression, in that the natural minor scale has a diatonic bVII just like the mixolydian scale. This quality is merely borrowed to resolve to a major tonic instead of a minor tonic. In addition, the bIII G major chord substitutes well for the iii chord in E mixolydian, which is G#dim. The notes of G#dim are G# B D; the notes of G major are G B D, meaning that they share two notes. Also, D is the V chord of G major; arguably, there is some secondary dominant action in the D going to a G in the manner of a V going to its I. However you slice it, the bVII – bIII – I progression sounds great (see, also, the Kinks’ “All Day and All of the Night).
- Using a major V chord in mixolydian as part of a progression to the I
- Modulating up a whole step
- bVII – bIII – I